Colitis in horses refers to inflammation of the colon. It is an extremely serious condition and if left untreated, 90% of affected horses will die. With an early diagnosis and the correct treatment, horses can go on to make a full recovery.

Clinical signs

  • Sudden onset Diarrhoea
  • Colic, inappetence and lethargy precede the diarrhoea usually
  • Possible temperature
  • Severe dehydration
  • Laminitis (as a result of the toxaemia)

Colitis can affect adults of all ages but horses between the ages of 2 and 10 years old are more often affected.

Early diagnosis is crucial and your horse will be referred to an equine referral hospital for intensive treatment as soon as there is a suspicion of the condition.

Possible causes include

  • NSAID (Bute) toxicity
  • Certain antibiotics
  • Change in diet
  • Stressful event
  • Salmonella
  • Clostridial
  • Encysted small redworms (Cyathostomes)

If the underlying cause can be identified then it can either be removed e.g. halting the administration of antibiotics, or treated e.g. worming. Treatment involves supportive care.

  • Intense fluid therapy
  • Replacement of lost protein
  • Anti-endotoxic drugs
  • Possible antibiotics

Rapid referral and institution of appropriate treatment measures improve the prognosis for horses with acute colitis. However, affected horses can deteriorate rapidly even in the face of the correct treatment. Complications of the endotoxaemia such as laminitis can be very difficult to control and treat. Sadly the outcome is sometimes not favourable.

Download the "Colitis" information sheet